JavaScript: Calling the unnamed
How does this look like?
o[""]()
A bit like a syntax error, eh? Or an emoticon of some sort. Well, it's valid JavaScript code.
JavaScript objects can have an empty string as a name for a property/method. So if you create an unnamed method called "", you can't call it using the dot notation, but you can, using the brackets.
So type this in your Firebug console:
var o = {
"": function(){
console.log('here')
}
}
then call the unnamed like o[""]()
It works!
Reminds me of the Wizard of Earthsea a little bit where you had to know the true names of things in order to do the wizardry.
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August 17th, 2007 at 4:18 am
“Reminds me of the Wizard of Earthsea a little bit where you had to know the true names of things in order to do the wizardry.”
or as in Eragon too
nice article btw ^^
August 17th, 2007 at 7:53 am
Yeah, since the [] square brackets allow you to access any “key” member of the object, any unique key works… including [""] empty string, even [null] works, as does [true] and [false].
Now, if there were only some real useful purpose for this… hmmm
August 17th, 2007 at 3:34 pm
True, can’t think of any purpose. Apart from job security by writing unmaintainable code
Here’s another one from the “this is not a syntax error” department:
alert("test"[1])And another one: http://www.wait-till-i.com/index.php?p=284
September 13th, 2009 at 12:29 am
Weird. I wonder if there’s some sort of compression/optimization value to this. One less variable “name” in there. Definitely odd to look at though.